Polyester film is an excellent plastic film, which can be applied as a peripheral material of a computer, e.g. keyboard, panel protection film, electrical insulative material for a panel back light module, or a magnetic substrate such as a computer magnetic tape. Alternately, the polyester film can be applied as food package, plated metal film, electrical insulative material, stationery, another livelihood industry, or another industry.
In general, the polyester film has excellent properties, e.g. high tensile strength, good impact resistance, high melting point for being used at a higher temperature. As such, the polyester film may serve as a protective material or a substrate material. Next, the polyester film has high transmittance, brightness, and smooth surface for being used in tag, adhering, printing, or the likes. The polyester film also withstand a high voltage, thereby being an electrical insulative material for wrapping wire, an insulative tape, a motor transformer, a capacitor, or the likes. The polyester film is not dissolved in organic solvents. Moreover, the polyester film has excellent acid resistance and oil resistance.
Since 1953, biaxial oriented polyester film is developed for various fields. The biaxial oriented polyester film is widely applied in electronics, equipments, magnetic records, packages, plate making printings, photosensitive materials due to its excellent physical and chemical properties.
The biaxial oriented polyester film is the major packaging material for high performance application or higher level products. For example, the biaxial oriented polyester film may serve as a brightness enhancement film substrate of a backlight module in a panel flat display (PFD), a protection film of optical degree and release film for a polarizer plate, an ITO substrate of a touch panel, and the likes.
The biaxial oriented polyester film for the PFD should simultaneously meet the requirements of high transmittance and low birefringence. In other words, a novel biaxial oriented polyester film is still called-for.